Levels of integration in electronics have continued to increase because of advances in circuit design and fabrication. The technology for fabrication of ICs has provided a vehicle for integrating a relatively large number of circuits and functions into an IC. As a result, present-day ICs might contain hundreds of millions of transistors. To provide a mechanism for coupling the various transistors and circuits, ICs include a variety of interconnect, such as metal layers, metal traces, etc. The increase in the number of transistors has led to the increase in the number of metal layers and interconnects.